The answer is no, there is no such filter.

What you want to remove actually matters - and "minerals/chlorine/etc." is just half a step more actionable than saying, "I want to remove stuff".

Residual chlorine doesn't leave spots on glass and fixtures.

Hard water minerals such as calcium and magnesium does leave deposits. To prevent that you need a water softener. There's no "filter" or electronic gadget that will do that for a shower other than a water softener that uses salt.

I live in an area with hard water and got Showerguard glass for my shower. After more than three years of use the glass still looks pristine and I do NOT squeegee after every shower. It gets cleaned once a week when my cleaning lady comes.

Other than that I haven't noticed any particular build up on my tiles or counters or fixtures but I would think that wiping them off once a week when you clean would prevent any build up. Of course certain finishes are going to show water spotting more than others

Thank you...I DO have a water softener, BUT I still get crazy spots and buildup on fixtures. The only place it is clean is where I have a small reverse osmosis filter under my sink that feeds my fridge water faucet. To clarify my ask, I am looking to get rid of squeegeeing primarily. Thank you, Helen -- that sounds great. I'll give that a go.

Get a test kit from Amazon and see if your water softener is working properly. You are looking for a Hach 5-B total hardness test kit. Test a mix of hot and cold water from your shower. My water is 23 grains of hardness per gallon which is extremely hard, before I installed a water softener. Your water should be less than one grains hard if you have a water softener and you should not be seeing deposits.